John Calvin Commentary Psalms 133:3

"Like the dew of Hermon, That cometh down upon the mountains of Zion: For there Jehovah commanded the blessing, Even life for evermore." — Psalms 133:3 (ASV)

Like the precious ointment upon the head. Here we have clear proof that David, as we have just said, holds that all true union among brothers originates with God and has this as its legitimate object: that all may be brought to worship God in purity and call upon His name with one accord.

Would this analogy have been borrowed from holy ointment if its purpose was not to show that religion must always hold the first place? Any harmony, it is thus implied, that may prevail among men is tasteless if not filled with the sweet aroma of God’s worship. Therefore, we maintain that men are to be united among themselves in mutual affection with this as the great end: that they may be placed together under the government of God.

If there are any who disagree with these terms, we would do better to oppose them strenuously than to purchase peace at the expense of God’s honor. We must hold that when the Priest is mentioned, it is to suggest that harmony originates in the true and pure worship of God. Meanwhile, by the beard and skirts of the garments, we are led to understand that the peace which springs from Christ as the head is spread throughout the entire Church.

The other image, of the dew falling upon Mount Zion and Hermon, signifies that a holy unity not only has a sweet aroma before God, but also produces good effects, just as the dew moistens the earth and supplies it with sap and freshness. We know that Moses said of Judea that it was not like Egypt, fertilized by the overflowings of its river, but a land that drank daily of the rain of heaven (Deuteronomy 11:11).

David suggests that human life would be lifeless, unprofitable, and wretched unless sustained by brotherly harmony. It is evident that Mount Hermon must have been rich and fruitful, as it was famous among places for pasture. Mountains depend principally for their fertility on the dews of heaven, and this was shown in the case of Mount Zion.

Finally, David adds that God commands His blessing where peace is cultivated. This means that He testifies how much He is pleased with harmony among men by showering down blessings upon them. The same sentiment is expressed by Paul in other words, (2 Corinthians 13:11; Philippians 4:9): “Live in peace, and the God of peace shall be with you.” Let us then, as much as is in our power, strive to walk in brotherly love so that we may secure the divine blessing.

Let us even stretch out our arms to those who differ from us, desiring to welcome them if they will only return to the unity of the faith. Do they refuse? Then let them go. We recognize no brotherhood, as I have already said, except among the children of God.